/**
 * Adds a vitest serializer for Shadow DOM.
 * You do not need to call this function directly - `@arcgis/lumina-compiler` will
 * configure Vitest to use this serializer automatically.
 *
 * @example
 * ```tsx
 * const { el, component } = await mount("arcgis-test1");
 * expect(el.shadowRoot).toMatchInlineSnapshot(`<p>1</p>`);
 * ```
 */
export declare function addShadowDomSerializer(): void;